The LTWOO V3 electronic groupset offers excellent electronic shifting performance at a fraction of major brand prices, but reliability concerns, poor customer support, and some technical quirks remain significant drawbacks.
Pros
- Excellent value for money compared to Shimano/SRAM
- Good shifting performance and speed when properly tuned
- Flexible compatibility with various cassettes, cranksets, and brake components
- Ergonomic shifters with comfortable hoods
Cons
- Poor reliability and high failure rates in early versions
- Very poor customer support and warranty service
- Water sealing issues, particularly in V1/V2 versions
- Mushy or unreliable shift buttons on early versions
Key Facts
- Uses standard 14500 800mAh 3.7V replaceable batteries
- Hydraulic brakes use mineral oil and are compatible with Shimano calipers
- V3 version features USB-C charging on the front derailleur only
Reviews & Ratings
The reviewer provides a long-term review of the LTWOO V3 eRX/eR9 electronic groupset after approximately 7,000 kilometers of use. He describes it as a semi-wireless Chinese groupset with shifters communicating wirelessly to derailleurs that are hardwired to a seatpost battery. Overall, his experience has been very positive, finding it well-made, functional, and enjoyable to use, though he notes some minor issues.
AI Summary
Pros
- Well-made and holding up well to use
- Light and efficient shifting
- Front and rear shifting is very good
- Rubber moldings for the hoods have stayed in really good condition
- The accompanying app is pretty good and allows fine-tuning of derailleur position for each gear and adjustment for different cassette types (9-13 speed)
- System is cheap compared to major brands (cost him £375 for shifters, derailleurs, brake calipers, and battery holder)
- Derailleurs are less bulky than some competitors because they don't carry individual batteries
- Rear derailleur can handle large cassettes (he uses a 34 and believes it could go bigger)
- Convenient magnetic charging via supplied cable (on his version) that can use a standard phone charger or power bank
- Hydraulic brake calipers work very well with cheap, effective organic pads
Cons
- Parts are more functional than pretty, not winning awards for industrial elegance
- Very light action on the shift buttons caused accidental gear changes when riding over bumps with hands resting on them
- The charging lead failed (it contains electronics for LED status), requiring a replacement to restore system function
- On rare occasions in cold weather, the rear derailleur has swung all the way to the biggest sprocket when selecting a lower gear, giving a much lower gear than expected
- LTWOO does not have its own chainset (he used a separate carbon chainset from another manufacturer)
- Slightly clunky mounting system for brake calipers, using adapters marked front/rear to use the same caliper design for both
Key Points
- Model reviewed is the LTWOO ER9 (all aluminum) / eRX (with some carbon parts); they are functionally identical
- The reviewer used version 1; version 3 is now available with changes including USB-C charging directly to the front derailleur and firmer button action
- System is semi-wireless: shifters are wireless, front and rear derailleurs are hardwired to a battery in the seatpost
- Battery is replaceable (he mentions removing batteries to charge them externally when the charging lead failed)
- App allows programming: fine-tuning derailleur position per gear and adjusting for different cassette speeds
- Total cost for the groupset (with a separate chainset) was about £500
- The groupset is from a Chinese manufacturer relatively unknown in the West
The reviewer discusses the LTWOO V3 eRX eR9 electronic groupset as part of a broader overview of Chinese cycling components. He mentions it's an upgrade to the IR9 with some carbon elements, available for around 500-600€ for almost the entire groupset via AliExpress, and compares its feel to Shimano 105. He notes it uses a battery in the seatpost and has app control capability.
AI Summary
Pros
- Upgrade to IR9 with some carbon elements
- Available for around 500-600€ for almost the entire groupset
- Shifting feel is very comparable to Shimano 105
- Uses familiar two-button shifting (up/down)
- Has app control capability
- Can be ordered directly via AliExpress when available
Cons
- Battery must be installed in the seatpost and connected (doesn't have the advantage of a smaller derailleur or not needing two separate batteries for front and rear derailleurs)
Key Points
- Version 3 (V3) should be ordered
- Electronic groupset
- 2x12s/2x11s configuration
- Replaceable battery (installed in seatpost)
- APP programming/control available
- Shifting mechanism uses two buttons like Shimano
- Part of LTWOO's lineup of electronic groupsets
The reviewer briefly mentions the L-TWOO 2025 eRX Road Electronic Hydraulic Disc Brake Groupset 2x10-12 SPEED but does not provide detailed analysis.
AI Summary
The reviewer briefly mentions the L-TWOO 2025 eRX Road Electronic Hydraulic Disc Brake Groupset 2x10-12 SPEED but does not provide detailed analysis.
AI Summary
The LTWOO eRX/eR9 (V3) is a Chinese electronic road groupset known for its low price, typically $300-$500 USD on AliExpress with coupons. It features 11/12-speed compatibility, hydraulic disc brakes using mineral oil, and replaceable 14500 batteries. Key attributes include: price around $300-$500, weight varies by model (eR9 alloy, eRX carbon; eR7 is a mid-tier option), and it uses standard road standards with compatibility for various cassettes (up to 34T with modifications) and cranksets. The V3 version introduced USB-C charging on the front derailleur, improved shift buttons, and better water sealing, though reliability and warranty support remain common concerns. Recent reports highlight a recurring issue: the groupset can suddenly become unresponsive mid-ride, requiring a brief charger connection to 'wake up' the system. This is often caused by the battery holder slipping inside the seatpost, triggering BMS protection. Users recommend securing the battery holder with rubber mounts or bubble wrap. Additionally, the groupset does not support USB-C to USB-C (PD) charging; only USB-A to USB-C cables or OTG adapters work. Shifting performance is significantly improved with Shimano cassettes and chains, while aftermarket Chinese cassettes may cause hesitation. The groupset continues to mature, with newer versions featuring lighter brake calipers (about 70g lighter per caliper) and improved compatibility. However, users report ongoing challenges with firmware updates potentially bricking components, inconsistent firmware versions affecting compatibility, and difficult brake bleeding procedures. Despite these issues, the groupset offers excellent value for DIY enthusiasts willing to troubleshoot.
AI Summary
Pros
- Excellent value for money, offering electronic shifting at a fraction of Shimano/SRAM prices.
- Good shifting performance and speed when properly tuned, with crisp and fast shifts.
- Flexible compatibility: works with various cassettes (beyond 32T with mods), cranksets, and mineral oil brake calipers from other brands.
- Ergonomic shifters with comfortable hoods, appreciated by users with medium hands.
- Replaceable standard batteries (14500) allow easy swaps and avoid proprietary battery issues.
- The groupset is maturing with fewer reported issues over time, and newer versions like the ERX with upgraded brake calipers address earlier shortcomings.
- Supports a wide range of gearing setups, including 50/34 chainrings with 11-34 cassettes, with proper tuning.
- Emergency 'wake-up' procedure works: connecting a charger for a few seconds can revive a bricked groupset mid-ride.
- Lightweight options: ERX components are lighter than Shimano 105 Di2 equivalents (e.g., ERX RD 289g vs 105 Di2 RD 301g).
Cons
- Poor reliability and high failure rates, especially for early versions (V1/V2), with rear derailleurs dying from water ingress or other issues.
- Very poor customer support and warranty service from LTWOO, with sellers often unhelpful or ghosting customers.
- Water sealing issues, particularly in V1/V2 where charging ports allow water ingress, leading to failures.
- Mushy or unreliable shift buttons on early versions, and occasional software glitches causing erratic behavior.
- Weak chain tension in the rear derailleur cage, leading to chain slap and drops, especially compared to Shimano.
- Front derailleur adjustment difficulties, including rubbing issues and limited inward movement, particularly with standard chainlines.
- Firmware updates can potentially brick components, with reports of front derailleurs being killed during updates.
- Bleeding hydraulic brakes can be problematic, requiring specific techniques like using two syringes, ensuring the caliper bleed port is the lowest point, and loosening a small screw in the shifter lever.
- Inconsistent firmware versions and product compatibility, with some components (e.g., V3 shifters with V2 front derailleurs) not pairing correctly despite being the same type.
- V3 groupset can suddenly become unresponsive (brick) mid-ride, requiring connection to a charger to 'wake up' the system; likely caused by BMS protection triggered by battery contact loss or deep sleep.
- Battery holder can slip or fall inside the frame, especially with stiffer wheels or rough roads, causing micro-disconnections that trigger BMS protection and brick the groupset.
- USB-C charging does not support USB-C to USB-C (PD) cables; only works with USB-A to USB-C cables or via OTG adapter.
- Some users report persistent shifting issues with non-Shimano cassettes and chains; switching to Shimano components often resolves problems.
- Front derailleur cage has play in the inner chainring position, causing chain rub on largest sprockets even after adjustment.
Key Points
- V3 version features USB-C charging on FD (no RD port), improved buttons, and better sealing.
- Compatible with cassettes beyond 32T (e.g., 34T, 36T) with pulley wheel swaps or OSPW cage.
- Uses standard 14500 800mAh 3.7V batteries.
- Hydraulic brakes use mineral oil and are compatible with Shimano/other calipers.
- App allows fine-tuning, firmware updates, and gear protection settings.
- Components (eR9, eRX, eGR, eR7) are largely cross-compatible.
- New versions (2026) have updated brake calipers and gold logos.
- New V3 brake calipers are ~70g lighter per caliper than older V3 calipers.
- Firmware updates can risk bricking components; inconsistent versions affect compatibility.
- Brake bleeding requires specific techniques: use two syringes, ensure caliper bleed port is lowest point, and loosen a small screw in the shifter lever.
- Groupset can brick mid-ride due to BMS protection; connecting a charger revives it. Secure battery holder to prevent this.
- USB-C charging does not support USB-C to USB-C (PD) cables; use USB-A to USB-C or OTG adapter.
- ER7 weights: shifters 515g, FD 144g, RD 318g. ERX weights: shifters 477g, FD 139.8g, RD 289.2g.
- Shimano cassettes and chains significantly improve shifting performance over aftermarket Chinese components.
- Battery holder slipping is a common cause of mid-ride failures; use rubber mounts or bubble wrap to secure it.
Where to Buy
LTWOO V3 eRX eR9 2x12s / 2x11s Electronic Groupset, Road Electronic Groupset, Replaceable battery, APP programming
L-TWOO 2026 eRX Road Electronic Hydraulic Disc Brake Groupset 2x10-12 SPEED
Specifications
Attributes
Included Components
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